Film processing machine and method



Feb. 7, 1933. c. R. HUNTER ET AL FILM PROCESSING MACHINE AND METHOD Filed Oct; 16, 1931 5 Sheets-Sheet l [IF/221mm slllllllllll I II III lllll I l I I I l l Illllllllllllllllll lllllllllllllllll Feb. 7, 1933. c N E ET AL 1,896,525

FILM PROCESSING MACHINE AND METHOD Feb. 7, 1933. c. R. HUNTER ET AL FILM PROCESSING MACHINE AND METHOD 5 Sheets-Sheet 3 Filed Oct. 16, 1931 Feb. 7, 1933. c; R. HUNTER ET u 1,896,525

FILM PROCESSING MACHINE AND METHOD Filed Oct. 16, 1931 5 Sheets-Sheet 4 n'vento 12 5 W m M B] 6 rw w Atlarney;

Feb. 7, 1933. c R HUNTER ET AL 1,896,525

FILM PROCESSING MACHINE AND METHOD Filed Oct. 16.. 1951 5 Sheets$heet 5 3: :5 EE- 2; I351;

W Jwtuy J mow m Patented Feb. 7, 1933 UNITED STATES PATENT OFFICE CHARLES ROY HUNTER AND ROBERT M. PIERCE, OF LOS ANGELES, CALIFORNIA,

ASSIGNORS TO UNIVERSAL PICTURES CORPORATION, OF UNIVERSAL CITY, CALI- FORNIA, A CORPORATION OF NEW YORK FILM PROCESSING MACHINE AND METHOD Application filed October 16, 1931. Serial No. 569,162.

This invention relates to machines for, and methods of, treating photograph films, and particularly films in the form of elongated tapes such as are used in motion pictures.

An object of this invention is to rovide a commercially successful method 0% producing duplicate negatives or positive motion picture films by the inversion process.

It is common photographic practice to develop an exposedfilm by convertin the material in the film that has been acte upon by light, into dark or opaque substance; Hence the film, after development, is a negative;

that is to say, the light portions of the original scene show dark in the film and the dark portions of the original scene show light in the film. It is the practice to then prepare final prints from the negative by exposing the sensitive film 'to light transmitted through the negative and developing the print in the same general manner as the original negative was developed. Since the image in the negative is a reversal of the actual image and the image in the final print is a reversal of the image in the negative, there have been two reversals, thus making the final print similar to the original image, or a positive as it is commonly termed.

The above method of producing prints of motion picture film is disadvantageous in that all of the final prints must be taken from the original negative, or a plurality of negatives must be made by printing from a positive made from the original negative. The first method is objectionable because there is a certain amount of wear on a negative during the printing process, and this laces a definite limit on the number of satis actory prints that can be taken from one negative. By the second process, as many negatives may be produced as desired, so that there is no need of taking a greater number of prints from any one negative than can be satisfactorily obtained. However, this method is open to the objection that there is a certain loss in quality during each printin process. In other words, due to imperfections in the material'of which films are constructed, a print from one film never carries quite as perfect an image as did the print from which it was oped into a positive rather than a negative,

then a large number of negatives could be produced from the original positive, and since the production of the negatives would involve only one printing operation, their qual ity would be substantially better than that of negatives made as the result of two consecu tive printing processes. It has been known for many years that by utilizing special proc-- esses, a positive image can be produced on a film. These processes are commonly termed inversion processes and may comprise the following. steps 1. Development 1. Developing 2. Washing 2. Washing 3. Bleaching 3. Bleaching 4. Washing 4. Washing 5. Clearing 5. Clearing 6. Fogging or 6. Fogging 7. Re-developing 7. Re-developing 8. Washing 8. Fixing 9. Drying 9. Washing l0. Drying It will be noted that the first process listed above comprises nine distinct operations, and the second process comprises ten distinct operations, as compared to four in the usual process, namely: Developing, fixing, wash-- mg and drying.

It is present practice to devolop motion picture film by continuous processes in which the film is passed continuously and successively through developing, fixing, washing and drying chambers.

Prior to applicants invention, as disclosed herein, and also in Patent 1,845,416, issued February 16, 1932, to Hunter and Pierce, on application Serial No. 423,729, filed January 27th, 1930, the only machines in commercial use for the continuous development of motion picture films involved the driving of a film through treating tanks at a relatively high speed by a large number ing fluids in elongated troughs, more satisfactory results could be obtained at much less expense than with the old type of machine then in general use.

In accordance with the present invention, applicants have discovered that their process, because of its simplicity and the small friction to which the film is exposed, enables them to continuously pass film through the large number of treatments necessary to' develop film's by the inversion process.

Various features of the invention will be made apparent by the following description taken in connection with the accompanying drawings, in which Figure 1 is a side elevational view ofour machine with portions broken away to indicate the operation.

Figure 2 is a schematic diagram showing the path followed by the film in traversing the different treating troughs in our machine.

Figure 2a is a schematic diagram showing the path followed by the film in traversing the different treating troughs in our machine when using an alternative process.

Figure 3 is an elevaticnal view of the rear end of the machine.

Figure 4 is a sectional view through one of the troughs of the machine showing the film guide pulleys.

Figure 5 is a side elevational view of one of the treating troughs showing the method of attachment of the guide wheels shown in Figure 4.

Figure 6 is a sectional view showing the positioning of guide members for guiding the-film and maintaining it at the proper depth within the treating troughs.

Figure 7 is a sectional view in the plane 7-7 of Figure 4.

First inversion process Referring to Figure 1, our machine comprises three troughs arranged in a vertical tier, with a drying compartment positioned above the top trough. Each trough is divided by a longitudinal partition into two compartments. Thus, referring to Figure 2, which shows the troughs spread out so as to disclose each one in plan view, the upper trough is divided by a central partition 4 to form a trough 5 for a clearing bath and a trough 6 for first developer. A cross partition 7 is provided adjacent oneend of the developer trough to form a small container 8 containing a stop solution. The second trough is also divided by a longitudinal partition 9 and a transverse partition 10 into a long trough 11 containing developer solution, a short trough 12 containing bleach, and a short trough 13 containing water or rinsing solution. The lower tro'ugh is divided by a longitudinal partition 14 into troughs 15 and 16 containing water.

The steps in the process of obtaining a duplicate negative or positive by one process with the use of our apparatus will now be outlined briefly with reference to Fig. 2. Exposed film enters from a magazine 17 into the upper front trough 6 containing developer and during its passage through the length of this trough the image is made visible. This ima e is, of course, opposite to the image from w ich the film was printed or exposed. When the negative image is fully developed, the film leaves the end of the developer tro'ugh 6 and enters the short trough 8 containing stop solution. Stop solutions are commonl used in photographic work for halting t e action of the developer and hardening the gelatine coating. From the stop solution trough 8 the film passes directly down into the trough 13 immediately-therebelow, containing water, and during its passage through this trough ail developer and stop solution is removed from the film. After leaving trough 13, the film enters the trough 12 containing bleaching solution. Numerous reagents are in common use for bleaching the film. Its purpose is to remove the negative image produced by the developer, and this removal is usually effected by a bleaching reagent which changes the re duced silver forming the dark portions of the developed picture into a silver halid or subhalid. At the time the film leaves the bleaching trough 12 the negative image has disappeared. After leaving trough 12 the film passes down into trough 16 directly therebelow. Trough 16 contains water which washes out the bleaching solution and silver salts previously rendered soluble with which the film became impregnated while passing through trough 12. Just before the film leaves the end of trough 16 it is exposed to light from a lamp 18, which is commonly termed the fogging lamp. The light from ICC) lamp 18 acfs upon the previously unexposed which the apparatus is located be maintained in total darkness, except for such non-actinic light as the films are insensitive to. It is obvious, however, that the fogging lamp 18 must produce actinic light in order to have the desired effect on the film. In order to prevent light escaping from the lamp 18 from that used in the original developer in trough reaching portions of the film prior to or during its passage through troughs 6, 8, 13. 12 and 16, it is necessary to locate the lamp 18 very close to the films in trough 16 and to use a source of light that produces very little heat. It has been discovered that a gaseous discharge lamp utilizing neon or a similar rare gas is peculiarly adapted for use in the present apparatus for the reasons that it produces very little heat and may be located very close to the films in trough 16 without heating them toany appreciable exten". Furthermore, although the light produced from such a lamp is sufiiciently actinic to produce the desired fogging effect on the films as they pass immediately thereunder, the actinic power of the light escaping from the lamp 18 is insufficient to fog the film before it reaches the end of trough 16.

After leaving the end of trough 16 the film passes upward and at the same time crosses over (the method of crossing over is disclosed in Figure 3 and enters the upper rear trough 5 which contains a clearing ath. The film, after it leaves the bleaching trough and the washing trough 16 is yellow in appearance and the clearing bath in trough 5, which may be sodium sulphite or bi-sulphite removes this yellow color. The film, after beingcleared, goes from trough 5 directly therebelow into the middle rear tray 18 which contains developing solution. This solution may or may not be substantially the same as 6. Since it is used it develop the image produced by the fogging lamp 18, it is commonly termed redeveloper. The re-developing of the film in trough 11 develops a visible image which is opposite to that produced by the ori inal development but is similarto the image rom which the film was printed. In other words, it is a positive image rather than a negative image. After being re-developed in trough 11 the film passes directly down into the lower rear trough 15 which contains water for removing from the film all traces of developer. After leaving the trough 15 the film passes upward between two downwardly directed air jets 19 and 20,"

which remove all surplus moisture from the film. The film thereaftercontinues upward to the drying chamber 21 at the top of the machine and is passed in a circuitous path through the drying chamber 21, during which time it is exposed to a controlled current ofdry air which removes all moisture from the film. The film is then withdrawn from the chamber onto a take-up reel 22.

Since the diagram of Figure 2 is purely schematic, it does not disclose how the film is actually moved through the machine.

Referring again to Figure 1, the film leaves the magazine 17 and passes over a brake pulley 23, thence between a tension pulley 24 and an associated pulley 25, around the tension pulley 24, back of pulley 25, thence through one or more guides 26 to an adjustable submersing pulley assembly 27 which comprises three pulleys 28, 29 and 30. Pulleys 28 and 29 are positioned above the level of the developing. solution in trough 6, but pulley 30 is positioned below the surface of the developer. The film, after leaving the guides 26, passes over pulley 28, back over pulley 29, and under pulley 30 into the developing solution. During its passage through the developing trough 6 the film, being submerged in the liquid and being of approximately the same specific gravity as the solution needs very little support. However, to maintain it at the proper level above the bottom of the tank, it passes over numerous guides 31. Atthe end of the developing trough 6 the film passes under a pulley 32, thence up out of the developing solution over a pulley 33 positioned above the partition 7, and thence down under a pulley 34, the lower side of which is submerged in the stop solution in trough 8. From trough 8 the film passes out over a pulley 35, thence down under a ulley 36, and under a pulley 37 submerged in the washing water in trough 13. The film passes through trough 13, being supported by guides 31 similar to those previously described, and at the end of trough 13 passes under a pulley 38, over a pulley 39 positioned above the partition 10, and thence down under the pul-- ley 40 into the bleaching trough 12. Thence it passes through the bleach, out under a pulley 41'at the exit end thereof, and up and over a pulley 42. From pulley 42 the film passes directly down under a pulley 43 and a pulley 44 into the rinsing trough 16. It is supported in its passage through rinsing trough 16 by guides 31 and at the end of the trough is fogged by the light from lamp 18. At the end of trough 16 it passes under a pulley Y45 and then up out of the trough and under a pulley 46 from which it extends crosswise up over the end of the machine and over a pulley 47 down into the clearing bath in trough 5. It passes through trough 5, thence under a pulley 48, over a pulley 49, down and under a pulley 50, and into the rear middle trough 11 containing the re-developer. It is submerged in the re-developer by a pulley 5'1, and passes to the end of the trough 11, thence. under a pulley 52, over a pulley 53 and down under a pulley 54 into the washing trough 15, It is submerged in the solution in'washing trough 15 by a pulley 55, passes through the solution supported by guides 31, thence under a pulley 56 at the end of the trough and a pulley 57 at the end of the machine. Thereafter it passes between the blower nozzles 19 and 20 up over a pulley 58 into the drying chamber 21. In the drying chamber it passes lengthwise through the drying chamber, being supported by pulleys 59, and thence out under a pulley 60, over a constantly driven sprocket wheel 61, which serves to draw the entire length of film from magazine 17 through the machine, and under a pulley 62 onto a wind-up reel 22.

Second inversion process The inversion process just described corresponds to the first process listed in the introduction of the specification. If the second process is used the apparatus employed is substantially identical to that disclosed in Figures 1 and 2, except that the lower front trough is divided into three sections instead of one.

Thus, referring to Figure 2a, in which the parts correspondlng to those in Figure 2 are given the same reference numerals with the sufiix a. The film leaves the magazine 17a and passes through the first trough 6a containing developing fluid. The original image is developed in trough 6a precisely as in the process disclosed in Figure 2. The film is then passed through stop solution in trough 8a, is washed in trough 13a and bleached in trough 12a. After leaving the bleaching trough 1211 the film tape, instead of being thoroughly washed, as was done in the first process, is given a short rinse in a trough 16b, and is then passed through a clearing bath in trough section 160 before being fogged. After leaving the clearing bath in trough 160 the film tape is washed a short time in the trough section 16d and is exposed to the light from the fogging lamp 18a. After being foggcd the film tape passes through directly to trough 5a, which in this process contains a second developer solution instead of the clearing bath. After leaving the second developer in trough 5a the film tape passes through trough 11a, which contains fixing solution. After being fixed the film tape passes down into trough 15a where it is washed, after which it passes between the dryer jets 19a and 20a and thence up to the-dryer compartment 21a where it is thoroughly dried. The film tape is then withdrawn from the dryer compartment 21a onto the take-up reel 22a, precisely as in the first process.

It will be a parent that the pulley equipment for gui mg the film tapes through the treating troughs shown in Figure 2a will be identical with that disclosed in Figure 1, ex-

cept that additional pulleys of the type disclosed at 32, 33 and 34 in Figure 1 will be required to guide the film out of trough 16?) into trough 16c, and out of trough 16c into trough 16d.

Miscellaneous improvements In the above description only one film has been traced through the machine. The machine is actually designed to handle simultaneously as many films as can be positioned side by side in the troughs. We have found it convenient to use troughs of such width as to accommodate five tapes of film, but this number may be varied between wide limits, if desired. Thus, Figures 4 and 6 disclose treating troughs of suflicient width to accommodate five tapes of film side by side. Figure 4, discloses how a plurality of pulleys (corresponding to pulleys 35, 36, 37, 46, 47 etc.) are mounted on a common shaft for guiding five films into or out of the fluids in the treating troughs, and Figure 6 discloses the construction of the guides 31 for maintaining the film tapes at the proper depth in the treating fluids while they pass longitudinally therethrough. In Figure 4 the outer wall of the trough 64, a floor of the trough and a center partition 66 are shown constructed of wood with the joints tongued and grooved to prevent leakage of the fluids to be contained. The pulleys 67 are preferably of bakelite and are mounted to rotate freely on a metal or bakelite shaft 68 which is secured by shoulders 69 to the walls 64 and 66 of the trough. The pulleys are maintained in proper separated position by separating bushings 70 and are centered with respect to the trough by bushings 71 which are secured to the shaft 68 by set screws, as shown. As disclosed in Figure 5, the end supports 69 are secured to the top edges of the troughs by screws 72.

The guides 31 disclosed in Figures 6 and 7 are preferably constructed of bakelite and are secured to a crosspiece 73 of rectangular cross section, the ends of which are fastened by screws 7 4 to the edges of the trough. The guides 31 are constructed in sections and are prevented from turning with respect to the rods 73 because of the rectangular shape of the latter.

It should be noted that both the pulleys 67 and the guides 31 are provided with shoulders 7 5 which engage the edges only of the film, thus preventing any possibility of the central portion of the film tape becoming scratched.

The manner in which the five film tapes are conveyed from the delivery end of one trough to the entry end of the succeeding trough, is clearly shown in the end view of the machine in Figure 3. The numbers on the pulleys in this view correspond to the numbers given in image on an exposed motion picture film illuminating said film tape durin Figure 1, so that the paths of the tapes may be readily followed.

We claim:

1. In a machine for developing a positive image on an exposed motion picture film tape by a single, continuous process, a plurality of elongated, shallow reservoirs, means for guiding film tape in substantially a straight line through each reservoir, roller means for guiding said film tape into the first of said reservoirs, roller means for guiding said film tape from each reservoir into the next succeeding reservoir,- a drying chamber, means for guiding the film tape from the last of said reservoirs into said drying chamber, and a single, take-up means engaging with the film tape beyond said drying chamber and serving as the sole means for moving the film tape through the machine; said successive reservoirs, in the order in which the film tape passes therethrough, containing developing fluid, washing fluid, clearing fluid, washing fluid, redeveloping fluid, and washing fluid, respectively, and a source of actinic light for illuminating said film tape between said washing and re-developing reservoirs.

2. In a machine for developing a positive tape by a single, continuous process, a plurality of elongated, shallow reservoirs, means for guiding film tape in substantially a straight horizontal line through each reservoir, roller means for guiding said film tape into the first of said reservoirs, roller means for guiding said film tape from each reservoir into the next succeeding reservoir, a drying chamber, means for guiding the film tape from the last of said reservoirs into said drying chamber, and a single takeup means engaging with the film tape beyond said drying chamber and serving as the sole means for moving the film tape through the machine; said successive reservoirs in the order in which the film tape passes therethrough containing first developer fluid, washing fluid, bleaching fluid, rinsing fluid, fixing fluid, and washing fluid, respectively, and a source of actinic light for .its passage between said clearing fluid an said second developer fluid.

3. In a machine for developing a positive image on an exposed motion picture film tape in a single continuous process, a series of open troughs containing solutions for developing, bleaching, and re-developing said tape, means for continuously drawing said tape through said successive troughs, and a gaseous discharge lamp positioned in close proximity to said moving film at a point in its travel between said bleaching solution and said re-developer solution for fogging image on an exposed motion picture film tape that comprises drawin the tape successively through a developing liquid, a washing liquid, a bleaching liquid, a second washing liquid, a clearing liquid, a re-developing liquid, and a third Washing liquid, from the exit end of said liquids without driving said film at intermediate points, the said film floating through said liquids in submerged position substantially horizontally and out of contact with the containers in which the liquids are held and being guided from one liquid to another, and exposing said film tape to fogging light during its passage between Taiddclearing liquid and said re-developing iqui 5. The method of producing a positive image on an exposed motion picture film tape that comprises drawing the tape successively through a developing liquid, a washing liquid, a bleaching liquid, a second washing liquid, a clearing liquid, a re-developing liquid, a fixing liquid, and a third washing liquid, from the exit end of said liquids without driving said film at intermediate points, the said film floating through said liquids in submerged position substantially horizontally and out of contact with the containers in which the liquids are held and being guided from one liquid to another, and exposing said film tape to fogging light during its passage between said clearing liquid and said re-developing liquid.

Signed at Universal City, Calif., this 28th day of September, 1931.

CHARLES ROY HUNTER. ROBERT M. PIERCE.

said tape as it passes said lamp without fogging it prior thereto.

4. The method of producing a positive 

